The E-Tree service is an Ethernet service that relates to multiple points. FIG. 1 shows a general structure of an E-Tree. An E-Tree includes one or more root User Network Interfaces (UNIs) and multiple leaf UNIs. A root UNI can communicate with any UNI; but a leaf UNI can only communicate with a root UNI. No communication between leaf UNIs is allowed. The E-Tree service cares about only attributes of the provided UNI, and does not care about detailed implementation in the network. The connection of an E-Tree is generally described through an Ethernet Virtual Circuit (EVC).
Currently, the protection solution specific to multi-point services in the prior art generally protects the E-Tree service by switching the whole tree. That is, when a fault occurs anywhere on an E-Tree EVC, the whole service is switched to the backup E-Tree EVC. Switching of the whole tree exerts an impact on the UNIs that are not affected by the fault, thus deteriorating the quality of the E-Tree service.